Johnstone spent the second half of last season at Aston Villa as his United career comes to an endGetty Images

Sunderland have joined the race to sign Manchester United goalkeeper Sam Johnstone after becoming consigned to losing Jordan Pickford to Everton. Aston Villa, Bristol City, Leicester City, Leeds United and Watford have all been linked with a move for the 24-year-old, who is approaching the final 12 months of his deal at Old Trafford.

The Daily Mail understand the Black Cats are considering Johnstone as a potential replacement for Pickford, who is set to complete his move to Goodison Park this week. The England Under-21 international is expected to cost an initial £18.5m ($23.5m), with £11.5m in add-ons bringing the total price to £30m - a fee which will make him the third most expensive stopper in history.

Johnstone has never represented the senior United side since joining the club in 2009 as a young player. After signing professional terms in 2011, he has been sent out on nine separate loan spells to seven different clubs. Last season he spent the second half of the campaign at Aston Villa, where he made 22 appearances.

Villa are understood to be among a clutch of clubs hoping to secure a permanent deal for the ex-England youth international, who could be available for a fee of £5m. Leeds, meanwhile, are hopeful of making Johnstone their third summer signing.

Managerless Leeds have already secured permanent deals for defender Pontus Jansson and winger Hadi Sacko following their respective loan stints. Manager Garry Monk left the club just days after the conclusion of the Championship campaign and a replacement has yet to be appointed despite links with Aitor Karanka and Michael Laudrup.

Leeds' Championship rivals Sunderland have already lost two influential members of the squad which failed to stave off relegation, with Jermain Defoe set to join Bournemouth and Pickford expected to move to Everton. David Moyes resigned the day after the end of the Premier League season, stifling the club's recruitment drive.